ASoC: da7219: Improve pop/click performance for sensitive HPs

Currently on some headsets slight pops can be heard during DAPM
power-up/down. This can also be witnessed during the HP detect
procedure. This patch addresses the issue by adjusting DAPM power
sequencing slightly, the introduction of delays and use of
minimum HP gain to avoid such noise artefacts.

Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/da7219.h

@@ -777,6 +777,10 @@
 #define DA7219_SYS_STAT_CHECK_RETRIES	6
 #define DA7219_SYS_STAT_CHECK_DELAY	50
 
+/* Power up/down Delays */
+#define DA7219_SETTLING_DELAY	40
+#define DA7219_MIN_GAIN_DELAY	30
+
 enum da7219_clk_src {
 	DA7219_CLKSRC_MCLK = 0,
 	DA7219_CLKSRC_MCLK_SQR,
@@ -814,6 +818,7 @@ struct da7219_priv {
 
 	bool master;
 	bool alc_en;
+	u8 gain_ramp_ctrl;
 };
 
 #endif /* __DA7219_H */